1. Technical Field
The present invention relates to a technology for detecting properties of a liquid contained in a liquid container.
2. Related Art
There are liquid jet devices which are used to form predetermined characters, shapes, and images (which will be hereinafter collectively referred to as “images”) by jetting liquids contained in liquid containers through a jet head to recording media such as glass-made or resin-made substrates and clothes. An example of such a liquid jet device is an image forming device such as an ink-jet printer, which forms a predetermined image on a recording medium by jetting a liquid ink from a jet head.
In order to achieve a very user-friendly structure, there has been a demand for an ink jet printer configured so as to enable ink properties to be determined automatically. Ink properties are, for example, a composition of an ink, a remaining amount of the ink, and a presence or absence of clogging in an ink cartridge. JP-A 2003-3101 disclose inks having compositions that are suitable for particular types of recording media. When such an ink is used, it is necessary for an ink jet printer to be able to determine automatically whether the ink properties of an ink being used are suitable.
In a case of using an ink to form an image, it is necessary for a certain amount of ink to be present in an ink cartridge. For example, JP-B-3603432 discloses a technology of activating a switch when a liquid ink decreases to a predetermined remaining amount, so as to equalize a calculated remaining amount of the ink and an actual remaining amount of the ink. JP-A-7-232440 discloses a technology in which an optical detection element is provided at a position corresponding to an ink flow path where an ink flows inside a jet head. By this technology, an amount and a status of an ink are detected. Further, JP-B-3878950 discloses a technology of extracting an electromotive force to operate a toy by use of two electrodes, with a liquid being poured into a member of the toy; though this technology does not relate to image forming devices.
However, the technology JP-B-3603432 or JP-A-7-232440 requires a switching mechanism provided in an ink cartridge or requires an optical detection element provided in a jet head, which gives rise to a problem of an increase in cost of an ink cartridge.